Intratubular Germ Cell Neoplasia, Unclassified Type (IGCNU), in Prepubertal, Cryptorchid Testes: A 20 Year Experience at a Major Pediatric Hospital.
Rong Fan, Thomas M Ulbright. Indiana University, Indianapolis
Background: Maldescended testes frequently come to the attention of pathologists, especially in pediatric hospitals. It remains controversial if prepubertal testes develop IGCNU. We therefore reviewed our experience over a 20-year interval with maldescended, prepubertal testes that carried a diagnosis of IGCNU.
Design: With approval of the Institutional Review Board, we performed several searches in our computerized pathology database from January 1990 to December 2009 to identify all testicular and paratesticular lesions. Next we examined all cases carrying a diagnosis of IGCNU. All were in maldescended testes.
Results: Of 883 testicular and paratesticular specimens, 276 represented atrophy/cryptorchidism (236) or intersex disorders (40). Among these 276 specimens, 6 from 5 patients with cryptorchidism carried a diagnosis of atypical intratubular germ cells. Three patients had a known intersex disorder and, on review, the specimens met the morphological and immunohistochemical criteria for IGCNU. Review of the remaining 3 specimens from 2 patients, who lacked an established diagnosis of an intersex disorder, verified that the atypical germ cells in 1 case lacked the features of IGCNU but showed nuclear enlargement with hyperchromasia and frequent central position within the tubules; these cells did express fetal germ cell markers (OCT3/4, placental alkaline phosphatase, CD117) also expressed in IGCNU and likely reflect delayed germ cell maturation, as has been described in the gonads of patients with undervirilization syndromes. The last patient, who was not known to have an intersex disorder, had a right duplex dysplastic kidney with both upper and lower pole obstruction and bilateral undescended testes. Review of his testicular specimens obtained at 9 weeks and 4 months, showed dysgenetic features, with ovarian type stroma and malformed tubules as well as IGCNU. We therefore consider him to have a previously undiagnosed intersex disorder, a conclusion also supported by the surgeon's intraoperative impression. We therefore did not identify a bona fide case of IGCNU in prepubertal maldescended testes outside of a known intersex disorder or with findings highly suggestive of one.
Conclusions: Based on our experience it is questionable if legitimate examples of IGCNU occur in prepubertal testes apart from an intersex disorder. Careful morphological and immunohistochemical evaluation and correlation with clinical findings are essential in the examination of prepubertal cryptorchid testes to avoid overdiagnosing IGCNU.
Monday, February 28, 2011 1:00 PM
Poster Session II # 196, Monday Afternoon